西口 雄基

Abstract Optimism is typically conceptualized as a relatively static tendency regarding positive expectations about one’s future. However, recent studies suggest that optimism may meaningfully fluctuate within individuals over time. To date, little is known about the characteristics of such state optimism and potential cultural difference in state optimism. Accordingly, we developed a Japanese version of the State Optimism Measure (J-SOM) and examined its validity and the nature of intraindividual state optimism fluctuations; we also examined relationships between the J-SOM and other measures of mental health, including trait optimism. We conducted two online longitudinal surveys with different time intervals (weekly, n = 97; monthly, n = 99) targeting university students. Results were largely consistent between the two surveys. We confirmed high factor validity and internal consistency of the J-SOM. The J-SOM showed significant correlations in expected directions with other measures such as depressive mood and subjective happiness. In addition, intraindividual changes in the J-SOM were associated with changes in mood and quality of daily life. Importantly, these associations between intraindividual change in optimism and in other variables were minimal for trait optimism. We also found that state optimism, compared with trait optimism, tended to show larger intraindividual changes over 1, 2, 3, 4, and 8 weeks. In summary, this study developed a translated version of the SOM and validated it, and then showed, for the first time, that state optimism can fluctuate within individuals in daily life over a span of several weeks.

Abstract The Maladaptive and Adaptive Coping Style Questionnaire (MAX) is a comprehensive tool for measuring coping styles including three subscales: maladaptive coping, adaptive coping, and avoidance. This study developed a Japanese version of MAX and evaluated the relationship between the coping styles and psychopathologies between the Japanese sample and the German sample. For the cross-cultural comparison, we used the Japanese community sample and German data set acquired by Moritz et al. (Journal of Affective Disorders 191:300–307, 2016). Factor analysis was conducted with the Japanese version of the MAX. Referring to the original version, we hypothesized the three-factor structure. However, the results showed that the adaptive coping subscale had less similarity to the original version, whereas the maladaptive coping and avoidance subscales were similar to the original. As the result of cultural comparison, the Japanese participants showed more maladaptive coping and avoidance. Moreover, the maladaptive coping styles had weaker correlations with the psychopathologies in the Japanese sample than with those in the German sample in the present study.

生産年齢人口において自殺は主要な死因となっており，リスクの高い個人を発見して自殺を未然に防ぐ ことは倫理的な側面からも，経済的な側面からも，これからの経営において強く求められることである． 自殺したいという思考や自殺の具体的な計画を含む希死念慮は，自殺に最も密接に結びつくリスク要因の 一つである．その一方，日常的なネガティブ体験から「死にたい」という思考が連想される場合もある． 先行研究では死が連想されやすい傾向には個人差があることが示唆されており，さらにその個人差は決定 論的信念によって左右される可能性があるが，これを実証した研究は行われていない．そこで，本研究で は，ネガティブな思考や体験から死に関する思考が連想されてしまう傾向を計測する質問紙尺度である死 連想傾向尺度を開発した．さらに，縦断調査により，決定論的信念が3カ月後の死連想傾向の増加を予測 することが示された．本研究により，決定論的信念が死に関わる思考を増加させるリスク要因である可能 性が新たに示された．このような個人差の計測を行うことで早期に自殺リスクを発見し，ケアしていく方 法は企業や官公庁におけるメンタルヘルスの問題にも応用可能であると考えられる．

Lack of positive emotion is considered an important aspect of depression. Previous studies have reported decreased attention to positive information for individuals with depressive symptoms; however, such studies have not investigated whether decreased attentional allocation occurs even when participants are required to fixate centrally on items presented in the visual field. In the present study, the attentional window (i.e., the spatial distribution of attentional resources) was measured with a modified version of the digit-parity task. In this task, the participants had to fixate on the centrally presented emotional face stimuli, and they were required to respond to the peripherally presented targets. The results indicated that individuals with higher levels of depressive symptoms were slower to respond when a target appeared near happy faces, which suggested decreased allocation of attention. Moreover, decreased allocation of attention to positive faces was found only in depressive individuals, not in individuals with social anxiety. The present findings suggest that individuals with higher levels of depressive symptoms allocate less attentional resources to positive stimuli, even when they are required to attend to them.

加害型対人恐怖症（加害型TKS）とは，対人恐怖症のうち，自分が他者を害していると確信して対人場面を恐れるサブタイプである。このサブタイプは，社交不安症（SAD）と類似した病態を示しながらも，恐怖が他者指向であるという違いが指摘されてきた。しかし，加害型TKSとSADに特有の症状を個人のどのような要素が予測するのかは検討されてこなかった。そこで本研究では，BIS/BAS （behavioral inhibition/activation system）および過剰適応傾向に着目し，これらの変数がそれぞれに特有の予測要因となるかを検討した。大学生274名を対象に質問紙調査を実施し，対人恐怖症傾向，社交不安症傾向，BIS/BAS,過剰適応傾向，抑うつ傾向を測定した。重回帰分析の結果，BIS/BASはSADに特有の予測要因である一方，過剰適応傾向は加害型TKSに特有の予測要因であることが示唆された。これは加害型TKSとSADがそれぞれ特有の心理的メカニズムを持つ可能性を示唆する。

This investigation examined conflicting suggestions regarding the association between problems retrieving specific autobiographical memories and the tendency to retrieve the details of these memories. We also examined whether these tendencies are differentially related to depression symptoms. U.S., Belgian, Hong Kong and Japanese participants retrieved memories related to cue words. Responses were coded for if they referred to a specific event (i.e., an event lasting less than 24 h) and their details (What? Where? Who?). Across sites, and in meta-analyses, the retrieval of more specific memories was associated with retrieval of more details. Memories that were specific included more detail than non-specific memories. Across sites, retrieval of more specific memories and more detail was associated with less severe depression symptoms. Episodic specificity and detailedness are related but separable constructs. Future investigations of autobiographical memory specificity, and methods for alleviating problematic specificity, should consider measures of episodic detailedness.

The relationship between trait rumination and working memory has not been well established. Previous studies have shown that high ruminators have poor working memory in general, while others have shown that they have superior working memory ability. Therefore, we tested the hypothesis that high ruminators have an imbalanced working memory ability, with inferior updating and superior attentional control abilities. A total of 178 graduate and undergraduate students completed three updating tasks: spatial 2-back, running memory, and memory updating; three attentional control tasks: Stroop, Eriksen flanker, and antisaccade; and two short-term memory tasks: dot matrix and digit span. Results of the latent variable analysis did not show any significant relationships between working memory factors, maladaptive brooding, and adaptive reflection. However, we observed imbalanced working memory at the individual task level, and increased reflection associated with superior antisaccade task performance and poor Stroop task performance. These findings suggest that high ruminators have an imbalanced working memory ability across task-specific components inherent in each task, such as oculomotor inhibition. Researchers should investigate the relationships between trait rumination and working memory, especially the aspects of superior ability, in more detail in further studies.

In recent years, several attentional bias modification (ABM) studies have been conducted. Previous studies have suggested that explicit instruction (i.e., informing participants of the contingency of stimuli) enhances the effect of ABM. However, the specific working mechanism has not been identified. This is partly because reaction time (RT) data are typically reduced to an attention bias score, which is a mere difference of RT between experimental and control conditions. This data reduction causes a loss of information, as RT reflects various cognitive processes at play while making a response or decision. To overcome this issue, the present study applied linear ballistic accumulator (LBA) modeling to the outcomes (RT measures) of explicitly guided (compared to standard) ABM. This computational modeling approach allowed us to dissociate RTs into distinct components that can be relevant for attentional bias, such as efficiency of information processing or prior knowledge of the task; this provides an understanding of the mechanism of action underlying explicitly guided ABM. The analyzed data were RT-observed in the dot-probe task, which was administered before and after 3-days of ABM training. Our main focus was on the changes in LBA components that would be induced by the training. Additionally, we analyzed in-session performances over the 3 days of training. The LBA analysis revealed a significant reduction in processing efficiency (i.e., drift rate) in the congruent condition, where the target probe is presented in the same location as a negative stimulus. This explains the reduction in the overall attentional bias score, suggesting that explicit ABM suppresses processing of negative stimuli. Moreover, the results suggest that explicitly guided ABM may influence prior knowledge of the target location in the training task and make participants prepared to respond to the task. These findings highlight the usefulness of LBA-based analysis to explore the underlying cognitive mechanisms in ABM, and indeed our analyses revealed the differences between the explicit and the standard ABM that could not be identified by traditional RT analysis or attentional bias scores.

<p>Space-valence metaphor (e.g., bad is down) is embedded within cognitive and emotional processing (e.g., negative stimuli at a lower space capture visual attention more than those at upper space). Previous studies have revealed that motor action to vertical direction affects the emotional valence rating of stimuli with a valence corresponding to the metaphor, such as downward manual action that increases the negative rating of the stimuli. Previous studies also showed that motor action affects the valence rating only when introduced after the stimuli presentation. However, motor action before the stimuli presentation may affect visual selective attention. In the present study, we replicated the previous result; vertical or horizontal manual action introduced before the stimuli presentation does not affect the valence rating (Experiment 1). Moreover, we employed a modified version of the dot-probe task as a measure of visual selective attention to emotional stimuli (Experiment 2), where participants’ vertical or horizontal manual action triggered a pair of emotional words. Results revealed that an upward, not downward manual action promoted the selective attention to negative words, which was incongruent with the space-valence metaphorical correspondence. These results suggest that even though manual action does not affect the evaluative process of emotional stimuli prospectively, upward manual action introduced before stimuli presentation can promote visual attention to the subsequent negative stimuli in a way that is incongruent with the space-valence metaphor. Mechanisms underlying the metaphor incongruent effect and its directional anisotropy (i.e., no effect of downward action) have been discussed in the present study.</p>

Previous studies have indicated that “need for cognition” (NfC), which is the tendency to enjoy effortful cognitive activity, affects various cognitive processes and behaviors. However, the effects of NfC on mental adaptation have not been investigated. According to previous studies, it can be hypothesized that NfC decreases maladaptive self-focusing, which is called self-rumination, through increasing effortful control (EC) therefore, we hypothesized that NfC would indirectly inhibit self-rumination through the mediation of EC. As we expected, the results of a cross-sectional questionnaire study with 152 undergraduate participants indicated a negative indirect association between NfC and self-rumination through the mediation of EC. Secondarily, the present results revealed a direct positive association between NfC and adaptive type of self-focusing, which is called self-reflection. The present study is the first to propose the possible contribution of NfC to mental health through decreasing self-rumination and increasing self-reflection.

In the present study, we explored the linguistic nature of specific memories generated with the Autobiographical Memory Test (AMT) by developing a computerized classifier that distinguishes between specific and nonspecific memories. The AMTis regarded as one of the most important assessment tools to study memory dysfunctions (e.g., difficulty recalling the specific details of memories) in psychopathology. In Study 1, we utilized the Japanese corpus data of 12,400 cue-recalled memories tagged with observer-rated specificity. We extracted linguistic features of particular relevance to memory specificity, such as past tense, negation, and adverbial words and phrases pertaining to time and location. On the basis of these features, a support vector machine (SVM) was trained to classify the memories into specific and nonspecific categories, which achieved an area under the curve (AUC) of .92 in a performance test. In Study 2, the trained SVM was tested in terms of its robustness in classifying novel memories (n = 8,478) that were retrieved in response to cue words that were different from those used in Study 1. The SVM showed an AUC of .89 in classifying the new memories. In Study 3, we extended the binary SVM to a five-class classification of the AMT, which achieved 64%-65% classification accuracy, against the chance level (20%) in the performance tests. Our data suggest that memory specificity can be identified with a relatively small number of words, capturing the universal linguistic features of memory specificity across memories in diverse contents.

The autobiographical memory test (AMT) is a widely used measure to assess the specificity of autobiographical memories. Reduced Autobiographical Memory Specificity (AMS) or increased overgeneralization of memories is considered as a cognitive hallmark of depression. Therefore, reduced AMS is the subject of much psychopathological research, and is a promising target for psychological interventions. Although considerable evidence has been gathered on the clinical relevance of reduced AMS over the past decades, studies on AMS have been mainly conducted in Western populations, and few have been conducted in Asian populations. This could be because of the unknown psychometric properties of the AMT given cultural and language differences. Therefore, the present study examined the psychometric properties of the AMT in a Japanese community sample (N=1240). Our data replicated that (a) the AMT has a uni-factorial structure; (b) AMS has a small but statistically significant negative correlation with depressive symptoms; (c) AMS shows a significant declining trend as a function of age, which influences the magnitude of the association between AMS and depressive symptoms in older adults. These findings suggest that the AMT has robust psychometric properties across different languages and cultural backgrounds.

Previous studies have shown a negative correlation between effortful control (EC) and depressive symptoms. EC is defined as the efficiency of executive attention, which may be reduced by the attentional impairment associated with depression. However, the mechanism underlying this correlation is still unclear. We investigated the relationship between EC and depressive symptoms with the hypothesis that cognitive motivation, or need for cognition (NfC), is a possible mediator of this relationship. Participants were 178 Japanese university students. Each completed the Zung Self-Rating Depression Scale, Effortful Control Scale, and Need for Cognition Scale at baseline and follow-up assessments. Supporting our hypothesis, mediation analyses revealed a significant indirect effect of depressive symptoms on EC that was mediated by NfC. In addition, our data demonstrated a direct effect of depressive symptoms on EC. Longitudinal analysis indicated that an increase in depression and a decrease in NfC occurred synchronously, while NfC predicted an increase in EC over time. Depressive symptoms may decrease executive functioning and effortful control both directly and indirectly, the latter effect being mediated by motivation. These findings imply that a motivational deficit may partially explain the decreased EC found in people suffering from depression. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

Previous studies have shown that attentional bias modification (ABM) is effective in reducing negative attentional biases. However, the mechanisms underlying how ABM effectively reduces negative attentional biases are still unclear. In the present study, we conducted an ABM procedure that included a 3-day training session with a sample of nonclinical participants (N = 40) to investigate the effect of ABM on emotional and nonemotional attentional biases. Participants completed a modified dot-probe task with 2 different instructions (explicit or standard) during the training; their attentional biases were tested before and after the training. Only participants trained with explicit instructions showed a reduction in negative attentional biases in dot-probe task and an improvement in attentional disengagement from negative stimuli in gap-overlap task. On the other hand, attention toward nonemotional stimuli was only marginally improved by training with both explicit and standard instructions. These results indicate that explicit instructions may promote ABM training.

A previous study indicated that depressed people show a smaller inhibition of return effect (IOR) for negative stimuli in a spatial cueing task. According to Mogg and Bradley (2005), a depressive bias in attention is observed only when self-relevant negative stimuli are presented. To test this proposition, the present research compared the IOR of depressed people for negative trait adjectives and for other negative words. We found that depressed participants had a smaller IOR for trait adjectives than for other negative words. This result suggests that depressed individuals have difficulty in disengaging their attention from negative self-relevant stimuli.